The subject of this patent application relates generally to heating, ventilation and air-conditioning (“HVAC”), and more particularly to an evaporative HVAC apparatus.
Applicant(s) hereby incorporate herein by reference any and all patents and published patent applications cited or referred to in this application.
By way of background, evaporative coolers operate by releasing water into the air in order to obtain an acceptable degree reduction in air temperature, dependent in part on the humidity of the outside air. Relying upon the thermodynamics associated with the conversion of water from a liquid to a gas, the majority of evaporative coolers employ a fan or blower that draws hot outside air through a wet, porous media. So long as the outside ambient air remains dry—typically below thirty percent (30%) relative humidity—such coolers can provide cooling during even the hottest days of the year at a fraction of the electrical power requirements of compressive refrigeration coolers.
Operation of a traditional evaporative cooler has the blower drawing outside air into the housing of the cooler, typically after the air first passes through a wetted media. Water in the wetted media evaporates into the dry air as it passes through, cooling and humidifying the air in the process. The blower then exhausts the cooled air from within the housing and into the areas to be cooled, displacing the warm ambient air with the cooled, conditioned, and humidified air. Evaporative heaters operate in a similar fashion, only using heated water in the wetted media so as to warm the air that is exhausted.
Maintenance of a traditional evaporative coolers and heaters requires periodic cleansing of the water reservoir. The number of operating hours between cleanings is primarily dependent upon the operational environment of the device. Such cleanings are important to maintain the efficiency of the unit, as well as to prevent an accumulation of undesirable molds, fungus, and odors. Additionally, traditional evaporative coolers typically require large amounts of water to cool the air, which not only hinders water conservation efforts, but also adds considerable moisture in the building in which the cooler is installed. Traditional evaporative coolers are also typically only able to operate efficiently in areas where the humidity is below thirty percent (30%).
Therefore, a need exists for such an evaporative device—both cooling and heating devices—capable of operating efficiently regardless of the humidity level of the outside air, and without the requirements of having to frequently clean the device or move large volumes of air or water to achieve the desired air temperature.
Aspects of the present invention fulfill these needs and provide further related advantages as described in the following summary.